Cabassous squamicaudis ( Lund, 1845 )

Feijó, Anderson & Anacleto, Teresa Cristina, 2021, Taxonomic revision of the genus Cabassous McMurtrie, 1831 (Cingulata Chlamyphoridae), with revalidation of Cabassous squamicaudis (Lund, 1845), Zootaxa 4974 (1), pp. 47-78 : 62-63

Cabassous squamicaudis ( Lund, 1845)

Cerrado naked-tailed armadillo

D [asypus]. gymnurus: Wied-Neuwied, 1826:529 . Not Tatus gymnurus Olfers, 1818:220 ; name not available from Illiger (1815).

X [enurus]. squamicaudis Lund, 1843 :lxxxiv (preprint of 1845a:lxxxiv). Nomen nudum.

X [enurus]. squamicaudis Lund, 1845b:35 (preprint of 1846:93, Tab. L., Figs. 3 & 5 ). Wetzel et al. (2008) listed the type locality as “Rio das Velhas Floddal”, Lagoa Santa, Minas Gerais, Brazil.

Dasypus hispidus Burmeister, 1854:287 . Type locality “Lagoa Santa”, Minas Gerais, Brazil.

Dasypus loricatus J. A. Wagner, 1855:174 . Cited as “ Dasypus loricatus Natt. in mscrpt.” in synonymy; and equated with “ D. gymnurus Ill [iger]” on page 175.

Xenurus hispidus: Gray, 1865:378 . Name combination.

Xenurus loricatus: Fitzinger, 1871:239 . Name combination.

Xenurus latirostris Gray, 1873:22 . Type locality “ Brazils , St. Catherines ”.

[ Lysiurus (Lysiurus)] latirostris: Trouessart, 1898:1147 . Name combination.

[ Lysiurus (Lysiurus)] loricatus: Trouessart, 1898:1147 . Name combination.

[ Lysiurus (Lysiurus)] hispidus: Trouessart, 1898:1147 . Name combination.

Tatoua (Tatoua) hispida: Miller, 1899:5 . Name combination.

C [abassous]. loricatus: Palmer, 1899:72 . Name combination.

C [abassous]. hispidus: Palmer, 1899:72 . Name combination.

[ Cabassus (Cabassus)] latirostris: Trouessart, 1905:820 . Name combination.

[ Cabassus (Cabassus)] loricatus: Trouessart, 1905:820 . Name combination.

Lysiurus hispidus: Cabrera, 1917:59 . Name combination.

Cabassous lugubris: Talmage & Buchanan, 1954:77 . Part; not Ziphila lugubris Gray, 1873:23 .

Cabassous squamicaudis: Paula-Couto, 1950:537 . Name combination.

C [abassous]. u [nicinctus]. squamicaudis: Wetzel, 1980:323 . Name combination.

Type material. Among the material collected by Lund from Lagoa Santa, Wetzel (1980:346) selected the specimen ZMUC L-33 as the lectotype of Xenurus squamicaudis Lund, 1845b .

Type locality. Lagoa Santa , Minas Gerais, Brazil . Wetzel et al. (2008) further restricted to “Rio das Velhas Floddal”, Lagoa Santa, Minas Gerais, Brazil .

Diagnosis. C. squamicaudis is easily differentiated from other Cabassous species by its cephalic shield composed of numerous and small scutes (43-75) that extends toward the cheek region. The ears are rounded, overall dark with smooth ( Figure 7b ) or irregular edges. The carapace is uniformly yellowish brown to brownish, with 12–13 movable bands. The lateral of the body and limbs are hairy. The venter is overall dark with some individuals showing whitish spots. Tail has few scutes sparsely distributed and shows a pale tip in few individuals (~5%). The skull shows a marked lateral constriction at the maxilla level.

Geographic distribution. Cabassous squamicaudis occurs in Cerrado of San Pedro and Amambay departments, northern Paraguay ( Smith et al. 2011), open areas of southern Bolivia ( Maffei 2006), and in central Brazil. The specimen examined by Wetzel (1980:348) from Junin, Peru housed at BMNH [catalog number not informed] could not be located; only two Dasypus skulls are available from Junin (R. P. Miguez, pers. Comm.). The specimens from Bolivia listed by Wetzel (1980:348) and Anderson (1997:177) are in fact C. unicinctus . Nevertheless, its presence in the open areas of Bolivia was confirmed by Maffei (2006) based on an individual recorded in Santa Cruz department, in a Chiquitano transitional forest. In Brazil, this species has a wide distribution in Cerrado, with numerous records in Mato Grosso state. It is also commonly reported in Pantanal in Mato Grosso do Sul state ( Wetzel 1985; Tomas et al. 2009; Desbiez et al. 2018).

Cabassous squamicaudis inhabits open areas such as Cerrado stricto sensus physiognomy and it seems tolerant to disturbed areas of cultivated pastures. This species has been recorded in closer contact with C. unicinctus in transition zones with the Amazonian forest in the states of Mato Grosso ( Anacleto et al. 2013).

Remarks. Xenurus squamicaudis was described as an extinct species by Lund (1845b) based on fossil material collected in the caves of Lagoa Santa, but Wetzel treated it as the same small living Cabassous taxon present in Minas Gerais.

The karyotype described by Pereira-Júnior et al. (2009) –diploid chromosome number (2n) = 46–refers to Cabassous squamicaudis . Interestingly, this chromosome number is distinct to C. centralis (2n=62), C. chacoensis (2n=48, Luaces et al. 2010) and C. tatouay (2n=50). The karyotype of C. unicinctus has not yet been described.

Figures

FIGURE 3. Scatterplot of the first and second principal components (a) and first and second discriminant functions (b) of the log-transformed cranial measurements of Cabassous clustered by species.

FIGURE 5. Comparisons of external measurements (in mm and weight in kg) and number of scutes on the cephalic shield across Cabassous species Note that none of the adult specimens of C. chacoensis examined have external measurements available.

FIGURE 7. External morphological differences between C. unicinctus and C. squamicaudis. Note the distinct color of the carapace and face between species. C. unicinctus has a paler venter, and usually, exhibits a dark central spot. In this species, scutes are absent below the eyes, in the cheek region, and in the anterior portion of the snout. Photos by Murilo Passarelli and Teresa Cristina Anacleto.